Well, there a lot of options available to 'fix' this problem:
1) Strengthen her health by encouraging her to take vitamins and health tonic.
Add in light exercise and perhaps yoga.
You should join in as well, it's good for you too.
2) Like big boss sammy said, get a few more gfs on the side.
As a good man, I wld advise the first option but if option #1 dun work, well there's always option #2.
